Questions[ndp](server)

I am looking for a way to retrieve the MAC address of a specific host on a LAN network. I know its IPv6 address. Ideally I would like a way to trigger the Linux Kernel to perform the neighbor solicitation for me, then I could retrieve the host MAC address through the command ip -6 neighbour

Right now, the only way I found to trigger a neighbor solicitation is to try to establish a TCP connection to the host on a random port. But I do not find this solution really pretty:

curl --connect-timeout 1 "http://[fe80::1234%eth0]:12345"

I have installed 3 VM's on my PC.(Ubuntu 11.04).I want to setup an IPV6 network to review and test some of the IPV6 tools like NDPMonitor.(monitors ICMP messages of Neighbour Discovery Protocol.)

IP v6 addresses are as follows.

linux_router - fe80::a00:27ff:fed5:f7e9/64 labhack1 - fe80::a00:27ff:fed2:8bd1/64 labhack2 - fe80::a00:27ff:fed7:2f2d/64

The below commands have been run on both linux_router and labhack1.

sudo ip r a 2001:468:181:f100::/64 dev eth0

sudo vim /etc/radvd.conf /file looks like below./

interface eth0
{
   AdvSendAdvert on; /*means that we are sending out advertisments.*/

   MinRtrAdvInterval 5; /*these options control how often advertisments are sent*/
   MaxRtrAdvInterval 15; /*these are not mandatory but valueable settings.*/

   prefix fe80::a00:27ff::/64
   {
        AdvOnLink on;   /*Says to the host everyone sharing this prefix is on the sam local                       link as you.*/

        AdvAutonomous on;  /*Says to a host: "Use this prefix to autoconfigure your address"*/
   };
};

sudo sysctl -w net.ipv6.conf.all.forwarding=1

I try to do a

ping6 -I eth0 fe80::a00:27ff:fed5:f7e9

I get Destination unreachable: Address unreachable.I am not sure what I am doing wrong here.I am a beginner at linux administration.Basically I think I am missing whatever is analogous to physically connecting VM's.Any help that would point me in the right direction would be greatly appreciated.

IPv6 and RFC 2462 provide a means for hosts to configure their own IP addresses via stateless address autoconfiguration. To me this seems like the bee's knees, and it leaves me wondering why someone would want to go through the trouble of configuring a DHCPv6 server instead. I don't manage networks as a profession, so I'm guessing that there are some obvious simple reasons why one would want to support DHCPv6 that don't occur to me. Could someone please elaborate on what these reasons might be?

Unsolicited neighbor advertisements is necessary to facilitate rapid service address takeover in a HA cluster. For IPv4 (ARP) you can use "arping -U", but so far I've had no luck finding any tool that can do something similar for IPv6.

EDIT: After searching more maybe the question is: Is this tool needed for IPv6? To me it looks like NDP should be able to solve this by it self.

Suppose you've configured IPv6 proxy NDP on one of your Linux systems like so:

ip -6 neighbor add proxy 2001:db8:1234::5 dev eth1

How do you verify that the configuration took? ip -6 neighbor show doesn't appear to show proxy entries and ip -6 neighbor show proxy isn't a supported command.